The present invention relates generally to dispensing apparatus for use in connection with apparatus for applying coatings to motor vehicle window glass and more specifically to a spool arrangement for dispensing a continuous length of wiping means and associate support means for mounting the spool on the apparatus.
Window glass installed in present day motor vehicles typically incorporates a blacked out band extending around the peripheral edge portion thereof. In order to form this blacked out band, it is necessary to apply an initial primer coating to the window glass after which the finish coat is applied. Thereafter an adhesive may be applied if required and the glass installed in the motor vehicle.
Typically these coatings are applied to the window glass in an automated process wherein a quantity or bead of the desired coating is fed onto the surface of the glass in a liquid or semi-liquid form. Thereafter the coating is spread evenly over the desired area and allowed to dry. Alternatively, in other operations a supply of the coating material is fed to and applied by the wiping means itself.
In order to accomplish this operation, an articulated robotic arm is provided which carries an elongated strip of felt. The end of the felt strip is moved along the edge of the glass by the robotic arm and operates to evenly spread the coating material over the area of the glass to be covered. It is necessary that a new end of felt be presented for each successive piece of glass and hence the arm also carries feeder means which operate to periodically advance a new section of the felt at which time the previously used end portion is severed from the supply length. Heretofore these elongated lengths of felt have been carried in an elongated serpentine tube mounted on the arm. However, because the tube can only accommodate a single length of felt, typically about eight feet long, it has been necessary to shut down the operation to replenish the felt supply two or three times each working day. This repetitive shut down not only impedes the production process but also incurs additional expense in the form of man-hours to periodically check the supply remaining as well as to replenish same. While the use of longer supply tubes would result in reducing the frequency of replenishment, this has not been possible because the feed means will tend to slip and/or shred the felt due to the increased frictional resistance created by the sliding movement through the feed tube of longer lengths of such felt.
The present invention, however, overcomes these problems by providing a spool capable of carrying substantially longer lengths of felt typically on the order of 30-35 feet or even longer. Mounting means are also provided on the robotic arm in close proximity to the feed means to rotationally support the spool thereon. Preferably, the mounting means is designed to enable quick and easy replacement of the spool and also to provide a predetermined resistance to the rotational movement thereof whereby premature unwinding of the felt strip can be avoided. Further, because the spool is fabricated from materials which can be burned, disposal of used spools is easily accomplished.
The increased length of felt available substantially increases productivity as replenishment of the supply is now required only once every one or two days. Further, because the supply is contained on a spool which may be easily and quickly installed, the time required to accomplish this replenishment task is greatly reduced. Further, because the spool is readily visible even when the machine is in operation, visual inspections may be accomplished to insure an adequate supply remains without the need to shut down machine operation.
Additional advantages and features of the present invention will become apparent from the subsequent description and the appended claims taken in conjunction with the accompanying drawings.